Airborne Mosquito SS - Finished ! 25-01-12 (page 2)

Having got my unknown "Titanium Frame" from Ebay a couple of weeks back and with the help of several fellow RBers identified it as an Airborne Lancaster [EDIT 07/12 - or maybe it isn't !] I have decided to try something completely different and build up a single speed. Never tried it, ridden one or seen one in the metal but lets have a go. Having parted company with my previous titanium frame - a Merlin '93 - due to disc brake related dilemmas, this one is going to get the non retro treatment (as much as I can sensibly afford) so it can be geared up later and become my trail bike in the future. I also have a bit of a liking for gold so "Blinglespeed" it is.
If anyone with SS knowhow would like to offer some guidance on ratios - do I want a 16/18/20T ? - and chains - do I need a special single speed chain or can I use a 9 speed one I have ? - and tensioners - do I need one really ? - and chainset - is it ok to use a triple but with just the middle ring ? - then it would be most welcome !
Here's where I'm at at the mo. Frame plus Bontrager Switchblades, Hope headset, gold Hope stem and seatclamp and a remnant of the Merlin in the shape of Syncros post 'cos its the right size.

I don't know if any of this will be any use to you but you never know.....

Ratios - depending on what sort of riding terrain you have, obviously, but I'd start with a 32 tooth chainring (it's more or less the law ) and an 18 tooth sprocket and take it from there. If the climbs are too hard then go to 20T, at least to start with until you get into it more.
Just deal with spinning out at 16mph on the flats - it'll get you used to spinning high cadences. Unless of course everywhere you ride is flat - if it is, then you can gear up accordingly (like a 16 or 15 tooth sprocket).

Have you decided what cranks you'll be using? Rather than just use the normal middle ring on a triple I'd replace it with a singlespeed chainring, in the interests of greater chain security. In other words, one with full depth teeth. Something like this.

You'll need some way of adjusting chain tension and if you use a tensioner that fits on the mech hanger go for one that is fixed rather than the spring loaded type.
This sort

rather than this sort

The neatest solution (IMHO) is an eccentric bottom bracket (EBB) converter like the Forward Components or Trickstuff Eccentriker. Both of these need an external BB type crankset.

Excentriker and Forward Components review here.

However, I believe that the FC is no longer in production - I do know of an Excentriker going spare though .

The best chain, in my not-so-humble opinion is the KMC Z610 HX This one.

Wideish bars (660mm+) are a big advantage (or I think they are) and don't shove the saddle back too far - I find that it's easier to spin high RPM's with it further forwards and you don't need power in the saddle as any time that there's any appreciable climbing you'll be out of the saddle anyway.

There's more than one way to skin a cat, so I'll disagree with Andy over the ratios. His hills are bigger than mine though.
I run 33;17 on one bike and despite very little different to 34;17, it feels a lot easier, but still gets you places on the flat! It also has the advantage that with a 16.75" chainstay (pretty common) , you will need no tensioner with a very lightly worn chain.
I haven't used an Excentrika BB though I do run a Forward Components one, and highly recommend them. They are pretty easy to adjust and don't creak like some "proper" oversize EBBs. They don't have the same range of adjustment, so ratios still need some thought, or a half link.
Do get an SS specific cog and chainring, of equal wear, if not new, and a similar chain, though SS is not necessary. Correct chainline is crucial though, and with Velosolo spacers is easy to achieve.
SSing is addictive though. It makes life just that little less complicated, which can't be bad!

Plug your gear ratios in here: http://eehouse.org/fixin/formfmu.php

to make it complicated again.

That is brilliant info thanks very much !
I'm planning to give this a try without too much initial expense so will use my current chainset reduced to just its 32T middle ring and see you can pick up a SS conversion kit for about a tenner. So I'll plump for a 16T I think as this is intended to be more a trail and road bike. I presume this will work with a spare 9 speed chain I have ?
If the SS bug bites then I'm relived to see that a proper conversion with a middle ring, chain and non sprung tensioner shouldn't cost too much - although that Excentriker is a beautiful piece of kit so maybe Santa will bring it for me ! (send me a PM Andy )
Or if anyone just happen to have an equally worn middle, cog and chain going then I'm definitely interested.

suburbanreuben":1v8esdqf said:

There's more than one way to skin a cat, so I'll disagree with Andy over the ratios. His hills are bigger than mine though.

Click to expand...

And he's old and feeble too There, fixed that for you......

If you need a half link then this is the only one worth bothering with -


From here.

If you can get SS specific stuff, then it's well worth it. There's usually someone deciding that SS is not for them , selling some kit on. Similarly, if you decide you're not man enough, it's easy to sell.
If your chain does slip, this could be the result! :shock:
http://www.retrobike.co.uk/forum/viewto ... =aubergine

point taken !

Some more shiny bits for the build

Well apparently after some more great input from RB what I have here is not a Lancaster but a Mosquito. Going to put some more of it together hopefully tonight.

trek_y":br3bwxkh said:

Some more shiny bits for the build

Click to expand...